Bison are easily aggravated during their mating season, as one family learned the hard way during a visit to Yellowstone National Park. The two adults and two children make the mistake of getting too close to a bull during the rut, and ended up being chased between trees by the agitated animal.
A video of the incident, shared via Instagram account TouronsOfNationalParks this week, shows the animal charging with its rail raised and head bobbing in a characteristic display of aggression, narrowly avoiding trampling a young girl. In the clip, which you can see below, you can see the bison driving the visitors away in clouds of dust before eventually leaving the area.
The family was lucky to escape unscathed, and each year there are reports from US National Parks of other visitors who aren't so fortunate. Last year two people were gored by bison within a week at US National Parks, and in June an 83-year-old woman was injured in a bison attack at Yellowstone.
In its safety advice for Yellowstone, the National Park Service warns all visitors to stay at least 25 yards (23 meters) from bison and elk, and 100 yards (91 meters) from large predators like bears and wolves.
"Give bison space when they are near a campsite, trail, boardwalk, parking lot, or in a developed area," warns the NPS. "If need be, turn around and go the other way to avoid interacting with a wild animal in close proximity.
"Approaching bison threatens them, and they may respond by bluff charging, head bobbing, pawing, bellowing, or snorting. These are warning signs that you are too close and that a charge is imminent."
For more advice, take a look at our guides how to avoid being gored by a bison and wildlife safety: eight tips for unexpected encounters.
- The best binoculars: enjoy watching wildlife from a safe distance